Tissue closure device

ABSTRACT

A tissue closure device including a hub and first and second flanges extending therefrom. The hub extends along a central longitudinal axis between a proximal surface and an opposing distal surface. The first flange is frameless and extends from the hub adjacent the proximal surface thereof. The second flange extends from the hub adjacent the distal surface thereof. The first and second flanges are moveable between: a closed position, in which the first and second flanges extend radially away from the hub and are substantially orthogonal to the central longitudinal axis; and an open position, in which the first and second flanges extend longitudinally away from the hub in opposite directions from each other and are substantially parallel with the central longitudinal axis.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a divisional application of U.S. patent application Ser. No. 13/308,227, entitled “Tissue Closure Device”, filed 30 Nov. 2011, the disclosure of which is incorporated herein by this reference.

BACKGROUND OF THE INVENTION

1. The Field of the Invention

The present disclosure relates generally to tissue closure apparatuses and methods.

2. The Relevant Technology

During intravascular and other related medical procedures, catheters are typically inserted through an incision or puncture in the skin and underlying tissues to access an artery or vein, typically in the groin, neck, or subclavian areas of a patient. The catheter can be inserted through a puncture in the blood vessel and guided to the desired site to perform interventional procedures such as angiography, angioplasty, stent delivery, plaque removal, and infusion of a therapeutic substance.

Often these procedures are performed by inserting a hollow needle through a patient's skin and muscle tissue into the vascular system. A guide wire then is passed through the needle lumen into the patient's blood vessel. The needle is removed and an introducer sheath is advanced over the guide wire into the vessel. The catheter typically is passed through the lumen of the introducer sheath and advanced over the guide wire into position for the medical procedure.

After the procedure is completed and the catheter and introducer sheath are removed from the patient, however, the access hole must be closed to prevent hemorrhage. This is typically achieved by applying pressure over the blood vessel manually and then by applying a pressure bandage or a compressive weight. With conventional methods, the risk of post-puncture hemorrhage is high, which can cause considerable complications. The risk of complications is exacerbated by the concomitant use of anticoagulant medications, such as heparin or warfarin, and by anti-platelet drugs, which are commonly used following a procedure in order to prevent clot formation and thrombus and/or to treat vascular disease.

It is generally recognized that many currently employed vascular sealing methods and devices and other tissue closure methods and devices incompletely seal holes or wounds in vascular or other tissue. Achieving complete wound closure is particularly important in sealing arterial punctures, which are relatively high pressure systems. For example, under normal blood pressure, the arterial system has a pressure of about 120/80 mmHg or more. Failure to completely close arterial holes can result in hematoma, exsanguination, and in extreme cases, may result in catastrophic consequences, such as limb amputation and death.

In many conventional tissue closure devices, a metal frame is used to maintain the closure device in place within the opening of the vessel. While these closure devices may close the opening, the metal in the frame does not allow the closure devices to be bioerodable or bioabsorbable and may also not allow a subsequent re-entrance into the vessel at the same location, as is often required.

BRIEF SUMMARY

The present disclosure provides methods and apparatuses that are suitable for closure of vascular punctures or other openings in bodily tissues.

In one aspect of the invention there is provided a tissue closure device including a hub and first and second flanges extending therefrom. The hub extends along a central longitudinal axis between a proximal surface and an opposing distal surface. The first flange is frameless and extends from the hub adjacent the proximal surface thereof. The second flange extends from the hub adjacent the distal surface thereof. The first and second flanges are moveable between: a closed position, in which the first and second flanges extend radially away from the hub and are substantially orthogonal to the central longitudinal axis; and an open position, in which the first and second flanges extend longitudinally away from the hub in opposite directions from each other and are substantially parallel with the central longitudinal axis.

In another aspect of the invention there is provided a tissue closure device including a hub, first and second flanges extending therefrom, and a first biasing element associated with the first flange. The hub extends along a central longitudinal axis between a proximal surface and an opposing distal surface. The first and second flanges extend from the hub adjacent the first and second surfaces, respectively. The first and second flanges are moveable between: a closed position, in which the first and second flanges extend radially away from the hub and are substantially orthogonal to the central longitudinal axis; and an open position, in which the first and second flanges extend longitudinally away from the central section in opposite directions from each other and are substantially parallel with the central longitudinal axis. The first biasing element provides a biasing force to the first flange that is less than a retention force that maintains the first flange in the closed position.

In another aspect of the invention there is provided a method of closing an opening in a vessel wall of a body. The method includes a step of positioning a deployment apparatus through the opening in the vessel wall. The deployment apparatus has a lumen extending therethrough. A tissue closure device is positioned in the lumen. The tissue closure device includes a hub extending along a central longitudinal axis between a proximal surface and an opposing distal surface. A first flange is frameless and extends from the hub adjacent the proximal surface. A second flange extends from the hub adjacent the distal surface. The first and second flanges extend longitudinally away from the hub in opposite directions from each other and are substantially parallel with the central longitudinal axis. The method further includes a step of expelling the tissue closure device from the lumen and into the opening in the vessel wall, thereby causing the first and second flanges to extend radially away from the hub and to be substantially orthogonal to the central longitudinal axis so as to bound a channel therebetween that receives and seals the vessel wall that bounds the opening. The method further includes a step of removing the deployment apparatus from the body.

In another aspect of the invention there is provided a method of closing an opening in a vessel wall of a body. The method includes a step of positioning a deployment apparatus through the opening in the vessel wall. The deployment apparatus has a lumen extending therethrough. A tissue closure device is positioned within the lumen. The tissue closure device includes a hub extending along a central longitudinal axis between a proximal surface and an opposing distal surface. A first flange, which includes a first biasing element, extends from the hub adjacent the proximal surface, and a second flange extends from the hub adjacent the distal surface. The first and second flanges extend longitudinally away from the hub in opposite directions from each other and are substantially parallel with the central longitudinal axis. The method further includes a step of expelling the tissue closure device from the lumen and into the opening in the vessel wall, thereby causing the first and second flanges to extend radially away from the central section and be substantially orthogonal to the central longitudinal axis so as to bound a channel therebetween that receives and seals the vessel wall that bounds the opening. The biasing force of the first flange against the vessel wall sufficient to seal the vessel wall is greater than the biasing force imposed by the first biasing element. The method further includes a step of removing the deployment apparatus from the body.

These and other embodiments and features of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter.

Embodiments of the present invention may provide several advantages over conventional designs. For example, embodiments of a closure device according to the present invention may provide an improved, more complete closure of a tissue opening than prior designs. In addition, many embodiments of a closure device according to the present invention are made of a polymeric material and do not include metal, thereby allowing the closure devices to be completely bioabsorbable or bioerodable. Furthermore, the closure devices may also allow a subsequent re-entrance into the vessel at the same location if needed. Other advantages may also be provided by embodiments of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the present invention will now be discussed with reference to the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. In the drawings, like numerals designate like elements.

FIGS. 1A and 1B are perspective and cross sectional views, respectively, of a tissue closure device in a closed position;

FIGS. 2A-2D are top views of various tissue closure devices showing alternative shapes of the flanges in the closed position;

FIGS. 3A and 3B are perspective and cross sectional views, respectively, of the tissue closure device of FIGS. 1A and 1B in an open position;

FIG. 4 is a cross sectional side view of the tissue closure device of FIGS. 1A and 1B showing the movement of the flanges between the open and closed positions;

FIG. 5 is a cross sectional side view of an alternative embodiment of a tissue closure device in position within an opening in a vessel;

FIG. 6 is a perspective view of another alternative embodiment of a tissue closure device that includes a biasing element;

FIG. 7 is an exploded view of a tissue closure system according to one embodiment of the present invention; and

FIGS. 8A-8D are cross sectional views of a tissue closure device and a deployment apparatus, illustrating a method of closing an opening in the tissue wall.

DETAILED DESCRIPTION

As used in the specification and appended claims, directional terms, such as “top,” “bottom,” “up,” “down,” “upper,” “lower,” “proximal,” “distal,” and the like are used herein solely to indicate relative directions in viewing the drawings and are not intended to limit the scope of the claims in any way.

The present disclosure provides methods and apparatuses that are suitable for closure of vascular punctures or other openings in bodily tissues. In some embodiments, the closure elements are bioabsorbable.

Generally, the apparatuses and methods described herein can be used with any type of body tissue that has sufficient strength to be held together by the tissue closure devices described hereinafter. By way of example only, embodiments of the present invention can be used to close openings in tissues that have a wall or membrane function, e.g., pulmonary, intestinal, vascular, urethral, gastric, renal or other wall structures, or in membranes, e.g., amniotic or pericardial membranes. Openings in other types of tissues can also be closed using embodiments of the present invention. Although many types of body tissue can be closed by the methods and apparatuses disclosed herein, the description included herein refers to “vessels” for convenience.

Furthermore, the apparatuses and methods described herein can be used with large and small hole punctures or other openings in the body tissue. By way of example, the tissue closure devices envisioned herein can be sized to close holes from 5 French to 30 French or larger. It may also be possible to close holes of other sizes using the tissue closure devices envisioned herein.

Turning now to the drawings, FIGS. 1A and 1B show a first embodiment of a tissue closure device 100 for closing an incision, puncture, or other passage through tissue, such as, e.g., communicating with a blood vessel or other body lumen. Tissue closure device 100 comprises a hub 102 and a pair of annular flanges 104, 106 extending therefrom.

Hub 102 extends along a longitudinal axis 108 between a proximal surface 110 and an opposing distal surface 112. Proximal and distal surfaces 110, 112 can be substantially planar or curved. Proximal and distal surfaces can be substantially orthogonal to the longitudinal axis 108, as in the depicted embodiment, or extend at a non-orthogonal angle with respect to longitudinal axis 108. In addition, proximal and distal surfaces 110, 112 can be coplanar or non-coplanar. Hub 102 can be comprised of a polymeric material, hydrogel, LLA or CCA or other type of like materials. Hub 102 can also be bioabsorbable, if desired.

Annular flanges 104, 106, which will be referred to herein as proximal flange 104 and distal flange 106, each extend from opposite ends of hub 102. Proximal flange 104 extends annularly from hub 102 adjacent proximal surface 110. Distal flange 106 extends annularly from hub 102 adjacent distal surface 112. Each flange 104, 106 has a first surface 114 and an opposing second surface 116 extending from hub 102 to an annular perimeter edge 118. First surfaces 114 of proximal and distal flanges 104, 106 are the surfaces of the flanges nearest the corresponding proximal or distal surface 110, 112 of hub 102. That is, first surface 114 of proximal flange 104 is nearest proximal surface 110 of hub 102 and first surface 114 of distal flange 106 is nearest distal surface 112 of hub 102.

A perimeter surface 120 can extend between first and second surfaces 114, 116 at perimeter edge 118, or first and second surfaces 114, 116 can intersect at perimeter edge 118, as in the depicted embodiment. Similarly, second surfaces 116 of proximal and distal flanges 104, 106 can intersect at hub 102 or hub 102 can have a perimeter sidewall 122 between second surfaces 116 from which the second surfaces extend. In addition, first and second surfaces 114 and 116 can act as inwardly facing surfaces or outwardly facing surfaces, depending on the configuration, discussed below.

Each flange 104, 106 is comprised of a resiliently flexible material to allow tissue closure device 100 to be inserted into a vessel opening and then close and seal the opening, as described in more detail below. In one embodiment, flanges 104, 106 can be made of a polymeric material, a rubberized material, or the like. As described in further detail below, flanges 104, 106 can include a biasing element embedded therein to provide structure and aid in moving to the different positions. In other embodiments, such as the embodiments depicted in FIGS. 1-5, biasing elements can be excluded from within flanges 104, 106. In addition, flanges 104, 106 can be free of metal, if desired.

With or without a biasing element, flanges 104, 106 can be sufficiently rigid to be positioned where desired within the tissue, yet resilient enough to move between different positions once located within the tissue, as discussed below. Flanges 104 and 106 are configured to close vessel openings by adhering to or otherwise biasing against the vessel wall through surface tension between the flange material and the tissue and direct pressure from the surrounding tissue and/or fluid within the vessel pushing flanges 104 and 106 against the vessel wall. In some embodiments, flanges 104 and 106 are bioabsorbable and/or bioerodable. Flanges 104 and 106 can be integrally formed with hub 102 or connected thereto, e.g., by adhesive, welding or other attachment method known in the art.

Being comprised of a flexible material, each flange 104, 106 can move between a closed position and an open position. In the closed configuration, shown in FIGS. 1A and 1B, each flange 104, 106 extends radially away from hub 102 (i.e., in a direction generally orthogonal to longitudinal axis 108) so as to be generally planar. In this configuration, first surfaces 114 of flanges 104, 106 face generally longitudinally away from tissue closure device 100 in opposite directions, and second surfaces 116 face each other. As a result, in the closed configuration first surfaces 114 of flanges 104, 106 act as outwardly facing surfaces 123 and second surfaces 116 act as inwardly facing surfaces 125.

In the closed configuration, proximal and distal flanges 104, 106 can be substantially orthogonal to longitudinal axis 108 so as to be substantially parallel to each other, as shown in the depicted embodiment, or can extend at a non-orthogonal angle. Flanges 104, 106 can also be substantially planar, as in the depicted embodiment, or curved, e.g., to match the curvature of a body vessel. In addition, first surfaces 114 of flanges 104, 106 can respectively be substantially coplanar with proximal and distal surfaces 110 and 112 of hub 102. In one embodiment, flanges 104, 106 are resiliently biased toward the closed configuration. That is, without an external force applied to flanges 104, 106, the flanges will move to the closed position or remain in the closed position if already there.

As noted above, second surfaces 116 of flanges 104, 106 face each other in the closed configuration to form inwardly facing surfaces 125. In this configuration, second surfaces 116 (along with perimeter sidewall 122 of hub 102, if present) together bound an annular channel 124 therebetween that radially extends from hub 102 and has a mouth 126 disposed between perimeter edges 118 of proximal and distal flanges 104 and 106.

Flanges 104, 106 can be designed to have different shapes in the closed configuration. For example, FIGS. 2A-2D depict various flange shapes that can be used with tissue closure device 100. It is noted that the flange shapes shown in FIGS. 2A-2D are exemplary only and that other shaped flanges are also envisioned by the present application. In some embodiments, flanges 104 and 106 have a radially symmetrical shape around hub 102. For example, FIG. 2A depicts an embodiment of a tissue closure device 200 wherein each flange 202 has a substantially circular outer perimeter 204. FIG. 2B depicts an alternative tissue closure device 210 wherein each flange 212 has a plurality of fingers 214 separated by recesses 216 so that fingers 214 extend radially further away from hub 102 than recesses 216.

In some embodiments, flange shapes are not radially symmetrical. For example, FIG. 2C depicts an alternative tissue closure device 220 wherein each flange 222 is substantially oval. Other non-symmetrical flange shapes can also be used. In some embodiments, the flanges are radially offset from each other. For example, FIG. 2D depicts an alternative tissue closure device 230 wherein each flange 232 has four fingers 234, but the flanges 232 are radially offset from each other. That is, proximal flange 232 a is positioned so that fingers 234 a thereof are longitudinally positioned between fingers 234 b of distal flange 232 b. Other flange shapes can also be used.

FIGS. 3A and 3B show tissue closure device 100 in the open configuration. In the open configuration, each flange 104 and 106 extends longitudinally away from hub 102 (i.e., in a direction generally parallel to longitudinal axis 108) so as to generally form a cylinder; perimeter edge 118 of each flange forms the end of the cylinder. As such, the circumference of each flange at perimeter edge 118 is significantly less in the open configuration than in the closed configuration. As a result, the portions of each flange 104 and 106 nearest to perimeter edge 118 are compressed or otherwise bunched up (not shown) on the inside of the cylinder. In one embodiment, flanges 104 and 106 are positioned within the cylinder in the open configuration so that an open bore 300 is formed within each cylinder having a mouth 302. As such, the cylinder formed by each flange 104, 106 may be hollow or loosely filled in. In any event, in the open configuration first surfaces 114 of flanges 104 and 106 generally form any inner surface 304 of the cylinder and second surfaces 116 of flanges 104 and 106 generally form the outer surfaces 306 of the cylinders. As such, the second surfaces 116 of flanges 104 and 106 face generally radially away from tissue closure device 100 in the open configuration.

FIG. 4 shows the movement of flanges 104 and 106 between the open configuration, shown in dashed lines, and the closed configuration, shown in solid lines. As discussed above, second surfaces 116 of flanges 104 and 106 form outer surfaces 306 in the open configuration and inwardly facing surfaces 125 in the closed configuration, while first surfaces 114 form the inner surfaces 304 in the open configuration and the outwardly facing surfaces 123 in the closed configuration. Furthermore, annular channel 124 is either nonexistent or simply an annular depression in the open configuration.

FIG. 5 depicts an alternative embodiment of a tissue closure device 500. Tissue closure device 500 is similar to tissue closure device 100 except that flanges 104, 106 and hub 102 have surfaces that naturally curve to generally approximate the curvature of the vessel wall for which tissue closure device 500 is to be used. This embodiment can be particularly useful for sealing openings in smaller vessel walls, such as vessel wall 502 in the depicted embodiment. Tissue closure device 500 can be curved in a single direction, orbe curved in more than one direction. Ultimately, any shape that helps tissue closure device 500 better match the shape of the vessel or other tissue can be used.

FIG. 6 depicts another alternative embodiment of a tissue closure device 600. Tissue closure device 600 includes a biasing element that is embedded within one or both flanges 604 or 606 to bias the flange to the closed position. A biasing element is defined herein to include any type of biasing structure or element embedded within the flange and designed to bias the flange in a particular manner. The biasing element can be made of any substantially rigid material, including metal if desired. For example, tissue closure device 600 includes a biasing element 602 embedded within one or both flanges 604 or 606. Biasing element 602 can include a plurality of struts that are rotatably interconnected so as to form a loose, moveable, framework. The struts can be relatively rigid to provide support to flanges 604 and 606. Alternatively, biasing element 602 can be comprised of one or more wires, such as a wire mesh 610 in the depicted embodiment. The struts or wires 610 can be made of a metal, such as stainless steel or Nitinol, a nickel titanium alloy. Other materials may also be used.

In one embodiment, when using biasing element 602, the material used for flanges 604 and 606 can be much less rigid then when the biasing element is omitted. Biasing element 602 can be used to stop plastic deformation rather than force tissue closure device 600 to remain rigidly in place. That is, biasing element 602 can loosely hold tissue closure device 600 in place while flanges 604 and 606 close vessel openings by adhering to or otherwise biasing the vessel wall through surface tension between the flange material and the tissue. As discussed above, the blood pressure within the vessel or other force (such as other tissue on the outside of the opening) can cause direct pressure on flanges 604 and 606 to also adhere to or bias against the vessel wall.

Thus, although biasing element 602 can help bias flanges 604 and 606 to the closed position, the biasing force caused by biasing element 602 can be less than a retention force that maintains the flanges 604 and 606 in the closed position. In light of this, in some embodiments, the force provided by biasing element 602 is not sufficient to cause flanges 604 and 606 to seal the opening; that force is provided by the surface tension and direct forces discussed above. In addition, although biasing element 602 is depicted on both flanges 604 and 606, it is appreciated that biasing element 602 can be used only on one of the flanges, if desired. Tissue closure device 600 can be used for any tissue or vessel envisioned for any of the tissue closure devices discussed herein, and is especially suited for use in closing patent foramen ovales (PFOs).

A deployment apparatus can be used to position the tissue closure device within the opening to be closed and to deploy the device. For example, FIG. 7 depicts one embodiment of a deployment apparatus 700 that can be used with tissue closure device 100 or any of the other tissue closure devices discussed herein.

Deployment apparatus 700 can include a sheath 702 configured to receive tissue closure device 100 and a deployment member 704 configured to be received within sheath 702 and expel tissue closure device 100 once deployment apparatus 700 is positioned at an opening in a tissue, as discussed below.

Sheath 702 is substantially cylindrical, having a substantially rigid, semi-rigid, or substantially flexible sidewall 706 extending along a longitudinal axis 708 between a proximal end 710 and an opposing distal end 712. Sidewall 706 has an outer surface 714 and an opposing inner surface 716. Inner surface 716 bounds a lumen 718 that extends longitudinally through sheath 702 between proximal and distal ends 710 and 712. Lumen 718 is sized and configured to receive tissue closure device 100 therein and maintain tissue closure device 100 in the open configuration. A bleed back lumen, as is known in the art, can also be formed in sheath to aid in positioning the deployment apparatus within the opening in the vessel. See, e.g., bleed back lumen 806 shown in FIG. 8A.

Deployment member 704 extends from a proximal end 720 to a distal end 722 and is configured to be slidably received within lumen 718 of sheath 702. Specifically, during use, distal end 722 of deployment member 704 can be slidably inserted into lumen 718 of sheath 702 until distal end 722 of deployment member 704 abuts proximal surface 110 of hub 102 of tissue closure device 100, as discussed below.

During use, once sheath 702 has been positioned within the blood vessel or other tissue as indicated by the bleed back lumen or the like as discussed above, the physician or other medical personnel can push deployment member 704 distally within sheath 702. The ensuing distal force of distal end 722 of deployment member 704 against proximal surface 110 of hub 102 of tissue closure device 100 causes tissue closure device 100 to exit sheath 702 out of distal end 712 thereof, as is discussed in more detail below.

In some embodiments, sheath 702 can be the same introducer sheath used for the underlying medical procedure. As noted above, an original introducer sheath and guide wire are often used during the underlying medical procedure through which a catheter or other device is passed. As such, once the catheter is removed from the original introducer sheath, the introducer sheath can be kept in place and tissue closure device 100 can be inserted into the introducer sheath after the guide wire has been removed. Deployment member 704 can then be inserted into the introducer sheath to push tissue closure device 100 out of the introducer sheath and into the vessel.

Furthermore, even if the original introducer sheath is not used, the guide wire used therewith can be used to guide sheath 702 into the vessel. To facilitate this, once the original introducer sheath is removed, empty sheath 702 can be guided to the opening by receiving the guide wire into lumen 718 and moving sheath 702 down the guide wire into the vessel. The guide wire is then removed from lumen 718 and tissue closure device 100 and deployment member 704 are inserted into lumen 718 in a similar manner as discussed above.

Turning to FIGS. 8A-8D, a method of sealing and/or closing a passage through body tissue, such as an opening 800 communicating with a blood vessel or other body lumen 802 through a wall 804 thereof, using tissue closure device 100, will now be discussed. Applicant notes that the method disclosed herein is exemplary only and that other methods of sealing and/or closing a passage through tissue using any of the tissue closure devices envisioned by the present application can also be performed.

Initially, tissue closure device 100 and deployment member 704 are positioned within lumen 718 of sheath 702 such that distal end 722 of deployment member 704 abuts proximal surface 110 of hub 102, as shown in FIG. 8A and discussed above. Tissue closure device 100 is in the open configuration described above and remains in the open configuration by virtue of inner surface 716 of sheath sidewall 706 preventing flanges 104 and 106 from moving to the closed configuration.

While in this configuration, deployment apparatus 700 is inserted through a tissue tract into the body until sheath 702 is positioned within opening 800, as shown in FIG. 8A. If used, a bleedback lumen, such as bleedback lumen 806 can indicate when deployment apparatus 700 is correctly placed, as is known in the art. If a guide wire is used to help position deployment apparatus 700, sheath 702 can be positioned within opening 800 and guide wire removed before tissue closure device 100 and deployment member 704 are inserted into lumen 718.

As shown in FIG. 8B, once sheath 702 is in position within opening 800, a distal force, denoted by arrow 808, can be exerted on deployment member 704. Distal force 808 causes deployment member 704 to move distally within lumen 718, which, in turn, causes tissue closure device 100 to also move distally due to the abutment of distal end 722 of deployment member 704 and proximal surface 110 of hub 102. As tissue closure device 100 moves distally a predetermined distance, distal flange 106 exits lumen 718 at distal end 712. Upon exiting lumen 718, distal flange 106 is no longer constrained by sidewall 706 of sheath 702 to remain in the open position. As a result, distal flange 106 moves to the closed position due to its resilient nature and its biasing to the closed position. When distal flange 106 is in the closed position, second surface 116 of distal flange 106 faces the inner surface 810 of vessel wall 804 around opening 800.

One or more visual markers can be positioned on the distal end (i.e., the end that exits the body) of deployment member 704 to aid in determining when deployment member 704 has moved the predetermined distance for distal flange 106 to move to the closed configuration. Alternatively, radiopaque markers 812 can be positioned at distal end 722 of deployment member 704 and/or in tissue closure device 100. Markers 812 can be viewed via X-Ray or other imaging method, as is known in the art, to determine the location of tissue closure device 100 with respect to the vessel. Once it is determined that distal flange 106 has moved to the closed configuration inside body lumen 802, deployment apparatus 700 and tissue closure device 100 can be moved proximally to cause second surface 116 of distal flange 106 to come into contact and abut inner surface 810 of vessel wall 804 if this is not already the case.

As shown in FIG. 8C, once distal flange 106 has moved to the closed position and abuts inner surface 810 of vessel wall 804, a proximal force, denoted by arrows 814, can be exerted on sheath 702 while keeping deployment member 704 in place. This proximal force 814 causes sheath 702 to retract proximally from opening 800 in vessel wall 804, while tissue closure device 100 remains in place due to its abutment to deployment member 704. As sheath 702 moves proximally a predetermined distance, hub 102 and then proximal flange 104 exit lumen 718 at distal end 712 of sheath 702.

Once proximal flange 114 has been expelled from lumen 718, deployment apparatus 700 can be removed from the tissue tract. Determining when proximal flange 104 has exited from lumen 718 can be accomplished in a similar manner to that discussed above regarding distal flange 106.

Upon exiting lumen 718, proximal flange 104 is no longer constrained by sidewall 706 of sheath 702 to remain in the open position. As a result, as shown in FIG. 8D, proximal flange 104 also moves to the closed position due to its resilient nature and its biasing to the closed position, similar to distal flange 106. When proximal flange 104 is in the closed position, second surface 116 of proximal flange 104 can abut against the outer surface 816 of vessel wall 804 around opening 800.

Once tissue closure device 100 is in position within opening 800, vessel wall 804 around opening 800 is received within annular channel 124 formed between proximal and distal flanges 104 and 106. Thus, proximal and distal flanges 104 and 106 move from the open configuration to the closed configuration to close opening 800 in vessel wall 804. As noted above, in the closed configuration, proximal and distal flanges 104 and 106 close opening 800 by respectively adhering to or otherwise biasing against outer and inner surfaces 816 and 814 of vessel wall 804 through surface tension between the flange material and the tissue and direct pressure from the surrounding tissue and/or fluid within the vessel pushing flanges 104 and 106 against the vessel wall 804.

If a tissue closure device is used that has a biasing element, the biasing element can help move the flanges to the closed configuration. However, as discussed above, in some embodiments the biasing elements do not provide the force that causes flanges to ultimately bias against the tissue wall and close opening 800.

Embodiments of the present invention can also be used for closing a patent foramen ovale (PFO) in a person's heart. To do so, a catheter containing the tissue closure device is percutaneously inserted into a femoral vessel in the groin and then threaded through the vessel into the heart. Using imaging devices, the catheter can be positioned within the heart at the site of the PFO. Tissue closure device 100 can then be expelled from the catheter and deployed within the PFO in a similar manner to that discussed above with regard to FIGS. 8A-8D. Radiopaque markers can be embedded within tissue closure device 100, if desired, to aid in positioning and deployment.

Although the present invention has been described in considerable detail with reference to certain preferred embodiments, it is contemplated that one skilled in the art may make modifications to the device herein without departing from the scope of the invention. Therefore, the scope of the appended claims should not be considered limited to the embodiments described herein 

What is claimed is:
 1. A tissue closure device for closing an opening in body tissue, the tissue closure device comprising: a hub extending along a central longitudinal axis between a proximal surface and an opposing distal surface; a first flexible yet resilient frameless flange extending from the hub adjacent the proximal surface thereof; a second flange extending from the hub adjacent the distal surface thereof; the first and second flanges being movable between: a closed position, in which the first and second flanges extend radially away from the hub and are substantially orthogonal to the central longitudinal axis, and an open position, in which the first and second flanges extend longitudinally away from the hub in opposite directions from each other and are substantially parallel with the central longitudinal axis.
 2. The tissue closure device according to claim 1, wherein the second flange is also frameless and flexible yet resilient.
 3. The tissue closure device according to claim 1, wherein the tissue closure device is biabsorbable.
 4. The tissue closure device according to claim 1, wherein the first and second flanges are substantially parallel with each other in the closed position such that the first flange and the second flange, together bound an annular channel.
 5. The tissue closure device according to claim 1, wherein the hub and flanges are free of metal.
 6. The tissue closure device according to claim 1, wherein the proximal surface is curved in the closed position to match the curvature of a vessel wall.
 7. The tissue closure device according to claim 1, wherein the first flange comprises a first surface and an opposing second surface that both extend to a perimeter end.
 8. The tissue closure device according to claim 7, wherein the first surface of the first flange is substantially coplanar with the proximal surface of the hub when in the closed position.
 9. The tissue closure device according to claim 8, wherein the second flange comprises a first surface and an opposing second surface that both extend to a perimeter end, and the first surface of the second flange is substantially coplanar with the bottom surface of the hub when in the closed position.
 10. The tissue closure device according to claim 1, wherein the first and second flanges are offset from each other when in the closed position.
 11. A tissue closure device for closing an opening in body tissue, the tissue closure device comprising: a hub extending along a central longitudinal axis between a first surface and an opposing second surface; a first flange extending from the hub adjacent the first surface; a second flange extending from the hub adjacent the second surface; the first and second flanges being movable between: a closed position, in which the first and second flanges extend radially away from the hub and are substantially orthogonal to the central longitudinal axis, and an open position, in which the first and second flanges extend longitudinally away from the hub in opposite directions from each other and are substantially parallel with the central longitudinal axis; and a first biasing element associated with the first flange, the first biasing element providing a biasing force to the first flange that is less than a retention force that maintains the first flange in the closed position.
 12. The tissue closure system according to claim 11, further comprising a second biasing element associated with the second flange, the second biasing element providing a second biasing force to the second flange that is less than a second retention force that maintains the second flange in the closed position.
 13. The tissue closure device according to claim 11, wherein the tissue closure device is bioabsorbable.
 14. A tissue closure device for closing an opening in body tissue, the tissue closure device comprising: a hub extending along a central longitudinal axis between a proximal surface and an opposing distal surface, a first annular flange extending from the hub adjacent the proximal surface, and a second annular flange extending from the hub adjacent the distal surface, wherein the first flange includes a first biasing element completely encapsulated by the first flange, the first biasing element being a single layer of wire mesh, the first and second flanges extending longitudinally away from the hub in opposite directions from each other and being substantially parallel with the central longitudinal axis such that the flanges generally form a cylinder and a continuous terminal edge of each flange forms each end of the cylinder, wherein the second flange does not have a biasing element.
 15. The tissue closure device of claim 14, wherein the first flange, the second flange, and the hub are integrally formed.
 16. The tissue closure device of claim 14, wherein the first flange and the second flange are substantially circular.
 17. The tissue closure device according to claim 14, wherein the tissue closure device is bioabsorbable.
 18. The tissue closure device according to claim 14, wherein the first and second flanges are offset from each other when in a closed position.
 19. A tissue closure system comprising: a tissue closure device as recited in claim 1 a deployment apparatus for positioning the tissue closure device, the deployment apparatus comprising: a sheath having a lumen extending therethrough, the tissue closure device being in the open position when disposed within the lumen; and a deployment member for expelling the tissue closure device out of the lumen, the tissue closure device moving to the closed position upon expulsion from the lumen.
 20. The tissue closure system according to claim 19, wherein the deployment apparatus further comprises a bleed back lumen formed on the sheath. 